AT&T software update

Hi everyone, last night I accepted AT&T's suggestion of updating my software, and now the phone has been for 8 hours backing up my data (it stopped at 8% in social feeds and hasn't moved) and of course I cannot use it, it wouldn't let me go back to main menu or any app. Don't know what to do, I already shut it down, took the battery off, it seems stopped there and honestly I don't mind not having this update done, I just want to be able to use the phone. What can I do?

Go a head and cancel the backup. Then plug your phone into your computer and perform a backup using the BlackBerry Desktop Software. While performing the backup follow these steps:

Launch BlackBerry Desktop Software

Click on Back Up Now

For the Backup Type, select Custom

Click the check box next to the Data Type column header

Scroll down to Social Feeds

Click the box to de-select this database

Click on Back Up

Thanks a lot for answering so quickly. The problem is that I cannot find a way of canceling the backup, it's just stuck. No matter what key I press, I try to reboot it and then it goes back again to the software update and stops at the same place. I even tried to start it in save mode but didn't work.